Excited geometries

An analysis of Eq and of the Clebsch-Gordan coefficients shows that for the appearance of non-zero density matrix elements /mm i at linear polarized excitation it is necessary that the E(different from 0 and 7t/2 see Fig. 5.3. Such excitation geometry implies the creation of tilted alignment (see Fig. 2.3(d)) which is described by alignment components... 

Thus, it is possible to optimize the phase-matching for the easier Raman-FID and CARS experiments and use the resulting S to calculate the correct excitation geometry for the Raman echo. 

Fig. 8 Excitation geometry for direct illumination of surface bound molecules. Image on the left shows the modified fiber optic cormector with a fluid port and adjacent optical fiber. Measured nearfield intensity distribution of the distal end confirms propagations of leaky modes...

Fig. 9 Excitation geometry for evanescent wave illumination of surface bound molecules. Sketch on the left show the smaller fiber at the periphery of the connector. Measured near-field intensity distribution shows the guided capillary modes...

Polarization EDXRF Polarized excitation geometry used with energy dispersive XRF employing low power tubes and X-ray end window tube with palladium or rhodium anode and beryllium window is claimed to lower the sulfur detection limit to 1 mg/kg. The precision of the method has not yet been established. 

If a direct excitation geometry is used for the analysis of automotive fuels, a Ti X-ray tube can be used. Typically those tubes use a power of maximum 30 W. Figure 2 shows an example spectrum for a sample with a sulfur content of 100 mg/kg. The peak-to-background ratio achieved in the example finm Fig. 2 is 2.5 1,... 

By introducing special excitation geometries, optimized sources and detectors, the picogram and even femtogram range of absolute analyte detection capacity can be reached in terms of concentrations, the same improvement factor can be attained, i. e. from the Lig g towards the pg g level under the best conditions. 

A quantitative treatment of acoustic and thermal wave generation is usually possible only for simple excitation geometries, as can be realized by laser excitation, using the basic equations of fluid mechanics and thermodynamics. 

The experimental setup for studying gas-surface scattering under those conditions implements a truncated prism to allow normal incidence of one of the beams onto the interface, as well as excitation of an EW with the other beam. In the experimental realization (Bordo et al. 2001) continuous wave lasers excited two adjacent transitions in Na atoms. In one excitation geometry (the "normal configuration"), the pump laser beam resonant to the... 

Figm 2 A schematic teptesentation of the excitation geometry at the objective and sample. The excitation light is focused by the objective on the sample through the immersion medium and the cover glass. Fluorescence is collected along the same optical path. 

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